Browsing through some of the blogs I read yesterday, I came across a handy bit of JScript posted by Jim Steger at Sonoma Partners. (Jim, as you may know, is the co-author of Working With Microsoft Dynamics CRM 4.0 and Programming Microsoft Dynamics CRM 4.0). Deploying this code as an OnLoad event for a form will show the number of notes in the notes container on the notes tab. It's easier to explain with a picture.
So take a quick hop to Sonoma's site if you would like to copy the code snippet to paste into your forms. Here's the link:
Nice work Jim!